Washington president Lawrence Simkins said: “We believe our proposal is extremely compelling and clearly in the best interests of Dominion and all of its stakeholders, including shareholders, customers, employees, and communities.

“If the transaction is consummated, it would provide Dominion shareholders with a substantial cash premium and offer superior value to that which Dominion could realize through ongoing execution of its plan or any other available alternative transaction.”

Dominion said: "Given the Company’s recent update on fiscal 2018 guidance and the complexity of Dominion’s assets, to indicate that diligence is confirmatory based on public records is highly questionable.

"It would also be entirely irresponsible of the company to allow a third party access to its confidential information without the benefit of customary agreements that protect the interests of shareholders and all of the company’s other stakeholders. "